Low Impact Development (LID): Keeping Water Local & Clean

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Transcript of Low Impact Development (LID): Keeping Water Local & Clean

Graphic Courtesy of Erie County Department of Environment and PlanningStormwater Runoff in your Street Affects your Recreation ActivitiesTransport of pollutantsReduced water qualityDrinking water impairmentsSwimming area closuresShellfishing areas pollutedAlgae bloomsDecreased aestheticsErosionFlooding hazardsImpacts of Stormwater“As a community grows, so does the amount of surface area covered by parking lots, roads and rooftops. Rainfall cannot soak through these hard surfaces; instead, the rain water flows quickly across them-picking up pollutants along the way-and enters ditches or storm drains, which usually empty directly and without treatment into local waterways.” (EPA, Benefits of LID Fact sheet)Because stormwater runoff is a leading cause of pollution in our waterways & water bodiesWhy does stormwater need to be managed?How?Regulates pollutant discharges into US watersThrough the National Pollutant Discharge Elimination System (NPDES) permits the EPA regulates stormwater discharges from municipal separate storm sewer systems (MS4s).Clean Water ActA MS4 is a system of drains, pipes, and ditches:Owned by a public entity (e.g. town)That collects and conveys stormwaterAnd that discharges into US watersWhat is a MS4?Main MS4 Permit RequirementsVisithttp://www.epa.gov/region1/npdes/stormwater/ma.htmlFor More Information On Your AreaAddress stormwater runoff in relation to development projectsDistribute educational material that address the impacts of stormwater runoff on the communityInform the public on steps they can take to reduce pollutants and stormwater runoffFor more information go to http://water.epa.gov/lawsregs/lawsguidance/cwa/tmdl/index.cfmWhat is a TMDL?Massachusetts DEP creates a list of impaired water bodies and their top pollutants. From this list a TMDL is created for each pollutant.How does MA address pollution from runoff?TMDL, total maximum daily load, is a daily limit on the amount of pollutant that can enter an impaired water body and still safely meet water quality standards .Applicants must consider low impact development (LID) techniques before selecting the appropriate best management practice (BMPs) for their development or redevelopment project“Loss of annual recharge to groundwater shall be eliminated or minimized through the use of infiltration measures including environmentally sensitive design, low impact development techniques…”MA Stormwater Management Standards for DevelopmentPhoto Credit: NSRWAThe Massachusetts Department of Environmental Protection strongly recommended the use of Low Impact Development techniques at this Target store in Hanover, MA because of its proximity to Third Herring Brook. Municipalities can strive for healthier stormwater regulations through the creation of stormwater and LID bylaws.Berkley: Encourages the use of nonstructural stormwater management and LID practicesStormwater Credits: incentive for developers to promote conservation of natural & open space areasDighton: Regulates post-development stormwater runoff dischargeRequires new development to maintain runoff characteristics equal to or less than pre-development characteristicsExamplesFor more information go to http://www.mapc.org/resources/low-impact-dev-toolkit/stormwater-bylawsCreated by municipalities to have stronger local stormwater regulations than regulations found at the federal and state level. Local stormwater bylaws encourage and support the use of LID, often through incentives to developers.Stormwater BylawsLow Impact Development (LID) is a way to manage stormwater that mimics nature.

It involves handling stormwater close to the source rather than piping it away.

Treats stormwater as a resource rather than a waste product.What is Low Impact Development?(Photo Credit: Cathy Bozek)This bioretention cell at a BSU parking lot allows runoff to infiltrate the ground, rather than run off into nearby roadways and waterways.LID can help limit polluted stormwater runoff by allowing more stormwater to infiltrate the ground rather than running off directly into the nearest waterway.How can LID help?(Facts and figures from the EPA, Benefits of LID factsheet )When vegetation and natural areas cover most of the land, such as in the Blue Hills (lower left), very little water, only 10% runs off into surface waters. Nearly half of the stormwater soaks into the soil. The remaining water evaporates or is released into the air by vegetation.When roads, rooftops and parking lots cover much of the land, more than half the stormwater runs off and flows directly into surface waters. In highly developed areas, such as Boston (upper left), only 15% of stormwater has the opportunity to soak into the ground.Hard surfaces speed the flow of runoff!LID Reduces the Area and Impact of Impervious Surfaces(Photo Credit: CT DEP)Redirect your gutter/downspout to flow over and into the ground rather than onto paved surfacesSet up a rain barrel to collect water from your roof downspout for later usePlant a rain garden (For more information visit http://nemo.uconn.edu/raingardens/index.htm)Wash your car on grass or gravel rather than pavementSweep your driveway rather than using water from a hose to clean itUse pervious surfaces like gravel to pave your driveway or walkway instead of asphalt or concreteYou can implement LID practices in your own home!LID in Your Own BackyardLID in Your TownMill River Park & RiverwalkTaunton(Photo Credit: Horsley Witten)(Photo Credit: Horsley Witten)(Photo Credit: MA EOEEA)(Photo Credit: MA EOEEA)AfterBefore(Photo Credit: Plymouth Department of Marine and Environmental Affairs)Bio-retention (rain garden) at Water StreetStormwater Regulations for the town favor LID practices.The town of Plymouth is incorporating LID into its projects with an over arching goal of cleaning up its harbor.Plymouth• Develop a site plan that reflects natural hydrology• Minimize impervious surfaces• Treat stormwater in numerous small, decentralized structures• Use natural topography for drainage-ways and storage areas• Preserve portions of the site in undisturbed, natural conditionsObjectives for Plymouth’s Stormwater Management GuideHighlight LID Principles(Photo Credit: Plymouth Department of Marine and Environmental Affairs)(Photo Credit: Plymouth Department of Marine and Environmental Affairs)Pond Road rain gardenStormwater runoff into Great Herring Pond via Pond Road prior to stormwater improvementsPond Road Rain Garden(Photos and Drawings Courtesy of: Plymouth Department of Marine and Environmental Affairs)Billington Street Stormwater Improvements The Department of Marine & Environmental Affairs acquired grant funding to design and construct stormwater management improvements along Billington Street including a new bioretention facility adjacent to Town Brook and a small pervious pavement parking area. This work will improve water quality in both Town Brook and Plymouth Harbor.(Photo Credit: Cathy Bozek)“There are clear benefits associated with the location of this project at a University Campus; the facility can be used easily as a teaching tool within the science curriculum at the school, and the concept of LID at the site is well aligned with the architecture of the science facility itself, which aims to be LEED silver certified.” (Horsley Witten)Bridgewater State University LID Parking Lot(Photo Credit: Cathy Bozek)BEFOREAFTER(Photo Credit: Horsley Witten)(Phote Credit – NSRWA)The Town of Pembroke has a stormwater pollution problem. Several of its waterbodies are on the Massachusetts List of Impaired Waterbodies. To help mitigate polluted runoff, Pembroke has implemented several LID projects.Pembroke Utilizes LID(Phote Credit – NSRWA)LID Techniques:Permeable paversGrassed paved geo-grid Previously, stormwater flowed down the boat ramp directly into Oldham Pond. The goal of the LID retrofit is to limit runoff entering the pond by decreasing impervious surface and pretreating stormwater.Oldham Pond Boat Launch(Photo Credit – NSRWA)Pembroke Town Hall“The green roof at Atlantic Wharf had an additional, somewhat unexpected, benefit. The neighboring hotel’s restaurant, Miel at the InterContinental Boston, keeps bees on the roof to provide honey used on the menu. Upon the installation of the green roof on Atlantic Wharf, the bees have been producing record amounts of honey. The green roof has contributed to creating an urban habitat for the bees, directly impacting their honey production and aiding in the success of urban bee programs.” (Boston Properties)Absorbs and collects stormwaterReduces flooding of, and damage to urban streetsReduces combined sewer overflows (CSOs)Reduces runoffProvides climate moderationReduces heat island effectProvides air purificationExtends roof lifeBenefits of Green Roofs(Photo Credit: Cathy Bozek)“Horsley Witten has designed LID stormwater management systems to address two problem areas at the school’s main parking lot. The designs consist of capturing flow from the parking lot in a small swale that leads to a bioretention system before discharging toward the agricultural fields below the parking lot. The Taunton River is located at the opposite side of the agricultural fields downstream of the parking lot. The new design will provide improved water quality treatment, detention, infiltration, and will reduce erosion at the edge of pavement.” (Horsley Witten)Bristol Agricultural High School Rain Gardens(Photo Credit: Cathy Bozek)(Photo Credit: Horsley Witten)Planting the rain gardenHow the area looked before the rain gardenCreating a Rain Garden(Photo Credit: Cathy Bozek) The Bristol Aggie rain gardens provided a hands on learning experience for the students. They learned about stormwater runoff and how LID can help. This learning experience can be repeated in other communities and get the public involved in the planning and installation process. Then community members can take what they learned back to their own backyards and other communities.Community Involvement in LIDWho Regulates Stormwater?Federal Level: United States Environmental Protection Agency(EPA) through the Clean Water Act State Level: Massachusetts Department of Environmental Protection(DEP) through wetlands and water quality regulationsLocal Level: Towns through stormwater and LID bylawsBoston Green RoofBoston is the first city in the nation to require a green building standard in the municipal zoning requirements. By amending Article 37 of the municipal zoning code, Boston requires that all large-scale projects meet the U.S. Green Building Council's LEED certification standards.Federal LevelFederal LevelFederal LevelState LevelState LevelLocal Level(Photo Credit: Plymouth Department of Marine and Environmental Affairs)(Photo Credit: Plymouth Department of Marine and Environmental Affairs)(Photo Credit: Plymouth Department of Marine and Environmental Affairs)Billington Street Rain GardenConstructionThe design, “includes impervious cover reduction and vegetated bioretention areas within the long islands between drive aisles, as well as underground recharge chambers to infiltrate runoff into the ground to the maximum extent practicable.” (Horsley Witten)LID Parking Lot Design(Photo Credit: Boston Properties)The green roof utilizes a tray system, for ease of maintenance of both the plantings and the roof membrane below. The native plantings were pre-grown in the trays then brought to the property and installed. The plants were selected to minimize the appearance of being in separate trays to make the roof look like a more cohesive garden. The trays can be removed when necessary to access the roof below and then reinserted once work is complete.After(Photo Credit: Boston Properties)BeforeAtlantic Wharf Green RoofTarget incorporates rain gardens and bio swales into the parking lot design.(Image Credit: City of Charlottesville)Financing LIDImplement LID techniques and break away from the traditional curb and gutter systemImplement:Narrower roadsShared drivewaysCurb cutsPervious pavementRain gardensBioswales(Photo Credit: City of Seattle)Seattle's Street Edge AlternativesA MS4 is not a:Combined Sewer Overflow System (CSOs)(Phote Credit – NSRWA)LID Techniques:Rain gardensPermeable paversGrassed level spreader infiltration trenchesDouble leaching catch basin with porous asphaltListen to Sara Grady of the North South Rivers Watershed Association discuss Pembroke's LID projectsRain Garden at Town HallLow Impact Development (LID):Keeping Water Local & CleanListen to Ellie Baker of Horsley Witten discuss the development of this parking lot(Design Credit: Horsley Witten)(Design Credit: MA EOEEA)Development costs are reduced by LID techniques because less money is being spent on traditional infrastructure (i.e. pipes, gutters, and water retention ponds).Often developers are able secure more buildable lots through LID planning and community induced incentives. Some LID techniques like rain gardens have similar costs to other landscaped areas. Prices for LID projects vary and communities should consider both construction and long term maintenance costs.Stormwater from the parking lot is flowing directly into the surrounding water body.LID TechniqueNon-LID Technique(Photo Credit: Plymouth Department of Marine and Environmental Affairs)(Photo Credit: The Nature Conservancy)(Photo Credit: The Nature Conservancy)(Photo Credit: The Nature Conservancy)Listen to Kim Tower, Plymouth's Environmental Technician discuss Low Impact Development in Plymouth(Photo Credit: The Nature Conservancy)For more information on the costs of different LID techniques refer to "The Economics of Low Impact Development: A Literature Review" by ECONorthwest http://www.econw.com/media/ap_files/ECONorthwest-Economics-of-LID-Literature-Review_2007.pdfManaging stormwater at the source through LID techniques rather than piping it away will provide long term economic benefits for your town.Keeping Water Local & Clean in Your CommunityPresentation Prepared by Julia KingTNC Intern, Northeastern UniversityFor More Information ContactCathy Bozek: cbozek@TNC.orgCasey Shetterly: cshetterly@TNC.orgList of LID sites in Massachusetts http://www.nature.org/ourinitiatives/regions/northamerica/unitedstates/massachusetts/explore/lid-sites-se-ma.xlsx

The Nature Conservancy's Work on the Taunton River http://www.nature.org/ourinitiatives/regions/northamerica/unitedstates/massachusetts/placesweprotect/southeast-massachusetts-preserving-pinelands-pond-shores-and-the-taunton-r.xml

Horsley Witten Taunton River Watershed Study http://www.horsleywitten.com/tauntonwatershed/index.html?refreshedIf you would like to learn more about the studies and projects mentioned in this presentation please visit:In Southeast Massachusetts, cities and towns, environmental organizations such as The Nature Conservancy, and other groups including schools and businesses are working to improve stormwater management by supporting and implementing Low Impact Development projects.Explore some examples of LIDMill river park & riverwalk, TauntonRain gardens, PlymouthLID parking lot, Bridgewater State UniversityRain garden, porous pavement, PembrokeGreen roof, BostonRain gardens, Bristol Aggie High SchoolWhy LID?Because LID has many benefits:Keeps water localManages stormwater at the sourceHelps to recharge local groundwaterImproves water quality by filtering out pollutants naturallySlows down stormwater runoff, allowing sediments to settleEliminates standing water, breeding grounds for mosquitoesReduces flooding and erosionRestores habitatImproves aesthetics in the areaLong-term economic savings1. Update Municipal Bylaws to Support LIDa. cluster zoning;b. subdivision regulations;c. wetlands regulations;d. design standards